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Downloading images

How to download images in high resolution

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Peter15

1-Oct-2017 18:46

When I upload photographic images Cardbox compresses jpeg for storage. That's fine until I want to extract these images and need to have them in their original high resolution. So far I have not found a way of extracting them other than in their compressed form. The original images are not in Amazon S3 though they are one OneDrive.

Can somebody help please?

Peter

John Francis

1-Oct-2017 19:43

I never put an actual image into Cardbox, partly for this reason; I simply include in the cardbox record a link to the original image in a separate folder.

The syntax for the link is something like: file:C:\photos\birds\chaffinch0241.tif

Hope this helps.

John Francis

bert

1-Oct-2017 19:53

Well, that is the blessing of JPG compression!
The time Cardbox was build, we did not have so much room for data. So it was more then necessary to compress. Cardbox compresses on high quality in my opinion a little too much. However: you can change the compression values by adding two lines in cardbox3.ini in your windows folder.
If you add:
[Image Compression]
JPEG Low Quality=90
JPEG High Quality=90
both compressions you choose now are JPG 90% in stead of the standard 80 and 60 or so. To reach maximum value, change it to 100. It still will decrease quality, because reading jpg 100 is still a jpg compression. My experience brings me to 90. This is a good comprise to quality/size.
Alternative: Add a second image field. First you use for storing a thumbnail, second for storing the original jpg file. Store the jpg as a non-imagefile. I did this for a 10000 image database. Worked fine. The only reason I stopped this system because the backup for the database (60 GB) took too much time.
I now build image banks by storing a thumbnail (longest side 800 pixels) in Cardbox and add a link to the original file into another field. The read process I do by a macro. Can also add a lot of EXIF then. For launching the original file I use Irfanview. Btw, I also use Irfanview for adding images. This because Irfanview resize/compress with much more quality then the Cardbox JPG compression does. But, as always, this is real scripting.
Regards
Bert

Chris H

2-Oct-2017 08:13

An aside from the previous communications re. image quality, I wanted to check my cardbox3.ini file for its compression settings but cannot find it on my computer. Where should it be? Can I create one using say Notepad? what else might be in such a file? Does Cardbox automatically 'look' in this file when opening??
Chris H

bert

2-Oct-2017 09:29

In my mail I wrote "cardbox3.ini in your windows folder.". So, there it is.
If it is not, create one with notepad. Cardbox will see it.
If you look in knowledge then you'll find cardbox3.ini again, but then used for a path to Ghostscript for making screen-dumps while importing pdf's. One search in Google to cardox3.ini tells us: http://www.cardbox.com/support/kb/importPDF.htm.
Regards
Bert

Charles Welling

5-Oct-2017 20:10

There's a much easier solution to circumvent the JPG compression of Cardbox and it's built-in.
What few people seem to know is that Cardbox DOES NOT re-compress a JPG file that is read from disk. It compresses:
- any non-compressed file format
- any file that is pasted into the image field using the clipboard

When a JPG is copied to the clipboard and then pasted into Cardbox, it will be re-compressed because Cardbox does not know it was originally a JPG. It's just a collection of pixels.
Any JPG that is read from disk however will be copied "as is".

For those of you who doubt it, try this:
First make sure that the option "store compressed" which activates a stronger compression is not selected.

1. Read a high-quality JPG from disk and look at the image size in bytes that Carbox reports. It will be the same as the original file. Do not save the record but:
2. Copy the original file to the clipboard and then paste it into Cardbox. The image size will be smaller and quality will deteriorate.
3. Then, looking at the second already compressed image, select "store compressed". The second image will become even smaller and quality will deteriorate further.
4. Switch to the first image (read from file) and try "store compressed on this image. It will not change.

There even no need to use an image programme to copy the original JPG to the clipboard. You may even copy the image that you've just read into Cardbox and then paste it. That one will be compressed because, again, Cardbox will no longer know that it was a JPG.

So, anyone who wishes to keep the original quality of a JPG (the size of the image is irrelevant) must read it from file, that's all.

bert

5-Oct-2017 20:34

You are right. **Only** in case of jpg (no Tif!) + reading the file + not any resizing + no resolution change in Cardbox while saving the record. And I' me sorry, this situation I did not met very frequent.

My advice is always: leave the original file untouched on disk, store a 800-1000 pixels high/wide image in you db with a link to your original. A database with 5000 unchanged images of camera's today, will soon be slow an irritant.
And keep this all ok and pretty fast, there are perfect ways to get this.
Regards
Bert

Charles Welling

6-Oct-2017 06:53

Of course someone should consider the disadvantages of storing large images in a database. But my remarks relate to images of all sizes. In other words, if someone wants to store small images in Cardbox but also wants to keep the original quality, then the simplest solution would be to read them from file, which is by all means the simplest way anyway.
You should be aware that changing the ini-file and setting the compression to 90 may actually increase storage size without improving the quality. Reading them from the original file keeps the original compression and quality, whatever they were.

And as to your observation:
"reading the file + not any resizing + no resolution change in Cardbox while saving the record. And I' me sorry, this situation I did not met very frequent."

Nobody should use Cardbox to resize or change an image because the resulting quality is poor. Cardbox is NOT a specialised image-processing programme. It's far better, and I believe it's common practice, to process the images before they are read. We use Irfanview to process the images (resize, watermarks etc) and then read them into the database using macros. Works perfectly and I'm talking about 600,000 ++ images.

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